1. Field of the Invention
The present invention relates to a digital recorder which is capable of digitally recording, reproducing and editing a digital audio signal.
2. Description of the Related Art
For recording, reproducing and editing an audio signal, a method is conventionally used, of recording an analog audio signal on a magnetic tape, reproducing the same from the magnetic tape and editing the recorded signal. Since this prior art involves an analog recording and reproducing process, deterioration of the sound quality is inevitable. Particularly, deterioration is prominent when the once-recorded audio signal is dubbed.
The use of the magnetic tape as a recording medium raises other problems that it takes time to reach a target editing point, and edition requires that a target recorded potion of the magnetic tape be physically cut and pasted or be copies to somewhere else before executing the edition.
The problem about the deterioration of the sound quality can be overcome by employing a method of digitally recording data on a magnetic tape. However, there still remains a shortcoming concerning the freedom of locating the starting point or edition due to the use of a sequential-access type recording medium.
In recent, there has been proposed a solution to the conventional problems which uses a hard disk or a magneto-optical disk as a memory medium for disk-recording a digital signal such as the above mentioned audio signal, a video signal or a musical instrument digital interface (MIDI) signal.
For example, the following U.S. Patent Applications have proposed several solutions to these conventional problems:
U.S. Ser. No. 07/690,710 filed Apr. 24, 1991 (Nobuo IIZUKA);
U.S. Ser. No. 07/752,876 filed Aug. 30, 1991 (Atsushi MIYAKE);
U.S. Ser. No. 07/795,983 filed Nov. 22, 1991 (Nobuo IIZUKA);
U.S. Ser. No. 07/807,053 filed Dec. 12, 1991 (Nobuo IIZUKA);
U.S. Ser. No. 07/850,682 filed Mar. 10, 1992 (Atsushi MIYAKE);
U.S. Ser. No. 07/850,684 filed Mar. 10, 1992 (Atsushi MIYAKE); and
U.S. Ser. No. 07/871,241 filed Apr. 20, 1992 (Nobuo IIZUKA and Hajime MANABE).
In the case of the use of the external memory medium such as the hard disk or the magneto-optical disk for editing the audio signal in sampling-data units, some device will be required because the above memory medium allows only a read/write process of data in so-called physical sector units.